New Post: applyNumberFormat flag in cellStyle XF field set to 0 by ClosedXML. Why?

As I understand it, the applyNumberFormat flag in a cellStyle XF record indicates whether or not a number format should be applied. When configuring a number format in ClosedXML (example link included below), the applyNumberFormat flag is set to 0. Excel doesn't have a problem with it, and will use the number format anyways. But I'm curious to know why ClosedXML does this. I support an old Windows application that reads this flag to determine if the number format should be used, and the number formatting won't work with any files created with ClosedXML.

https://closedxml.codeplex.com/wikipage?title=Styles%20-%20NumberFormat&referringTitle=Documentation